Baby hates belly time

Yasmin • I'm 21yrs old grown up with bad ibs which made me in constant pain growin up ended up with fibromyalgia 2 yrs ago and now I'm going to be a mum :)
My son is 8 weeks today and I keep getting told to do belly time. He can support his head quite well but still bit floppy but every time I do belly time he just crys he won't lift his head or anything he will just lay there crying. He will do it on me and he loves to be sat up looking around. Is there any other way I can strengthen his neck muscles?